Heritage Audio Herchild 670 Review: A True Fairchild Successor?

The Heritage Audio Herchild 670 is a modern recreation of one of the most legendary compressors in recording history—the Fairchild 670. This beast of a unit has been responsible for shaping countless iconic records, known for its silky smooth compression, natural warmth, and ability to glue a mix together like no other piece of gear. Heritage Audio set out to capture the essence of the original, offering the same tube-driven magic with modern reliability and accessibility.

But how well does it hold up against the original? And is it worth the investment for today’s studios? Let’s dive deep into everything the Herchild 670 has to offer.

The History Behind the Fairchild 670

To truly appreciate the Herchild 670, we need to look at its inspiration—the Fairchild 670. Designed in the 1950s by Rein Narma for Les Paul, the Fairchild quickly became a staple in high-end recording studios, finding its way onto countless classic records from The Beatles, Pink Floyd, Queen, and Steely Dan to modern legends like Daft Punk and Adele.

What made the Fairchild 670 unique was its use of massive vacuum tubes and transformers, allowing it to apply smooth, natural-sounding compression without artifacts or harshness. It excelled at gluing mixes together, adding depth, warmth, and a polished character that became highly sought after in mastering and bus compression.

However, owning an original Fairchild today is nearly impossible—vintage units cost upwards of $50,000, and maintenance is a nightmare. This is where the Heritage Audio Herchild 670 steps in—a faithful reproduction that brings the Fairchild sound into the modern era without the insane price tag and fragile components.

Build Quality & Design: A Tank in the Studio

The Heritage Audio Herchild 670 is a massive piece of hardware, just like its predecessor. It’s built like a tank, with an all-metal chassis and premium components that exude high-end craftsmanship. At nearly 20 rack spaces in size, it’s not exactly a compact unit, but neither was the original Fairchild.

Key Design Features:

• Authentic Fairchild-style knobs, VU meters, and layout – The interface is true to the original, offering the same workflow for engineers familiar with vintage hardware.
• Handwired tube circuitry – Uses 22 tubes and 9 transformers, just like the original, ensuring the same rich harmonic coloration.
• Heavy-duty build – This is not a lightweight replica; it’s designed for serious professional use.

One advantage of the Herchild 670 is that it’s a brand-new unit, meaning no dealing with aged, unreliable components or expensive repairs—a huge plus for anyone who’s ever owned vintage gear.

Sound Quality: The Analog Glue Your Mix Needs

If there’s one reason to buy the Herchild 670, it’s the sound. The tube-driven, vari-mu compression provides the same organic, three-dimensional character that made the Fairchild famous.

How Does It Sound?

• Incredible warmth – The Herchild 670 enhances low-end weight without making things muddy. It gives mixes a rounded, full-bodied sound that is instantly pleasing.
• Silky smooth compression – Unlike modern VCA or FET compressors, the vari-mu topology means compression feels almost invisible—perfect for transparent level control.
• Lush harmonics – The 22 tubes add natural harmonic distortion, giving a pleasing saturation to any source.
• Huge stereo image – The compressor adds depth and width to mixes, making them feel larger-than-life.

Unlike digital emulations or even modern compressors, the Herchild 670 adds a richness that is difficult to describe until you hear it in action. It’s never harsh, never artificial—just pure analog goodness.

Practical Applications: Where the Herchild 670 Shines

The Herchild 670 is one of the most versatile compressors out there, making it ideal for various studio applications.

1. Mix Bus & Mastering Compression

One of the most common uses for a Fairchild-style compressor is on the mix bus or during mastering. The Herchild 670 adds a cohesive, glue-like quality that makes the mix sound like a polished, finished record.

🔹 Tip: Use a slow attack and moderate release to add subtle compression and keep dynamics natural. A gain reduction of 1-2 dB is usually enough to add warmth and cohesion.

2. Vocals

The Herchild 670 is a fantastic vocal compressor, adding depth, sustain, and a smooth presence. It works wonders on lead vocals, group vocals, and even background harmonies.

🔹 Tip: Try using Time Constant setting 2 or 3 for smooth vocal control, without making the compression obvious.

3. Drums

Fairchild-style compressors are famous for their use on drum busses. The Herchild 670 thickens the low end, controls transients, and makes the kit feel glued together.

🔹 Tip: For a fat, punchy drum sound, try compressing the overheads or room mics with a slow attack and fast release—this will help retain transients while adding sustain.

4. Bass & Guitars

On bass, the Herchild 670 helps maintain consistency and warmth without killing dynamics. For guitars, it can add sustain and round out harsh frequencies.

🔹 Tip: Dial in a medium attack and a slow release for bass guitar to keep the low end controlled without over-squashing the dynamics.

Tips & Tricks for Getting the Best Out of the Herchild 670

✅ Use Parallel Compression – Try blending the compressed signal with the dry signal for a more natural feel.
✅ Experiment With Bias Control – The DC threshold allows fine-tuning of harmonic content, letting you add more color if desired.
✅ Try It on the Stereo Bus at Low Ratios – Even at subtle settings, the Herchild 670 makes a massive impact.
✅ Use It as a Limiter for More Control – With a fast attack, it can act as a transparent peak limiter while maintaining warmth.

Final Verdict: Is the Heritage Audio Herchild 670 Worth It?

The Herchild 670 is not just a compressor—it’s a piece of history, reborn for the modern studio. Heritage Audio has done an incredible job recreating the magic of the Fairchild 670, offering the same warmth, smooth compression, and unmistakable analog character without the sky-high vintage price tag.

💰 Is it expensive? Yes. Is it worth it? Absolutely.

For professional studios, mastering engineers, and anyone who wants the absolute best in analog compression, the Herchild 670 is a game-changer. Whether used for mixing, mastering, or tracking, it delivers the kind of depth, glue, and harmonic richness that digital emulations can’t match.

🔥 Final Rating: 5/5 – A must-have for serious studios.